copy_to_user() cannot return a negative value: it returns the number of bytes
that could not be copied.
Return -EFAULT on failure rather than the number of bytes that could not be
copied, as this seems more standard.
Signed-off-by: Cyril Roelandt <[email protected]>
---
drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c
index 8d3a218..77a3598 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c
@@ -62,7 +62,6 @@ static ssize_t ixgbe_dbg_reg_ops_read(struct file *filp, char __user *buffer,
{
struct ixgbe_adapter *adapter = filp->private_data;
char buf[256];
- int bytes_not_copied;
int len;
/* don't allow partial reads */
@@ -73,9 +72,8 @@ static ssize_t ixgbe_dbg_reg_ops_read(struct file *filp, char __user *buffer,
adapter->netdev->name, ixgbe_dbg_reg_ops_buf);
if (count < len)
return -ENOSPC;
- bytes_not_copied = copy_to_user(buffer, buf, len);
- if (bytes_not_copied < 0)
- return bytes_not_copied;
+ if (copy_to_user(buffer, buf, len) > 0)
+ return -EFAULT;
*ppos = len;
return len;
--
1.7.10.4
On Fri, 2012-11-16 at 04:26 +0100, Cyril Roelandt wrote:
>
> copy_to_user() cannot return a negative value: it returns the number
> of bytes
> that could not be copied.
>
> Return -EFAULT on failure rather than the number of bytes that could
> not be
> copied, as this seems more standard.
>
> Signed-off-by: Cyril Roelandt <[email protected]>
> ---
> drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
Actually, I already have a similar patch in my queue reported by Dan
Carpenter, and created by Josh Hay which fixes this issue. I should be
pushing the patch in my queue in the next week. Here is the patch I am
referring to:
ixgbe: eliminate Smatch warnings in ixgbe_debugfs.c
This patch replaces calls to copy_to_user, copy_from_user, and the
associated logic, with calls to simple_read_from_buffer and
simple_write_to_buffer respectively. This was done to eliminate
warnings generated by the Smatch static analysis tool.
Reported-by: Dan Carpenter <[email protected]>
CC: Dan Carpenter <[email protected]>
Signed-off-by: Josh Hay <[email protected]>
Cheers,
Jeff